Areas of the world that have sub-soil temperatures of 55° F or less open the opportunity
to construct a wine cellar that does not require supplemental cooling. A room temperature
between 50° F and 60° F with a relative humidity of 60% to70% will keep the cork
swollen and air from entering and spoiling the contents of the bottle. Any concrete bunker,
root cellar, or bomb shelter can offer the dank, dark, cool conditions ideal for the preservation
of fine wines.

If subterranean temperatures are too high or the room is to be built inside of an existing
basement, a vapor tight, insulated room is the best action. Standard stud wall construction
is acceptable, but the better the insulation the less energy will be consumed by the cooling
device. The use of high-R sheathing to line the inside will not only improve the insulation
but help to form a vapor barrier. It is best to line the entire interior with polyethylene
to prevent moisture loss. Exterior grade plywood can be used for paneling since the shelving
or racks should pretty much cover the walls. Real wood paneling can be used as well. Gypsum
board will have a tendency to mildew unless sealed with a mildew resistant paint. Racks
are constructed in such a way as to keep the bottles in a "reclining" position
so corks are wet and oxygen stays out.

One unique method of cooling the wine cellar is to run a loop of copper hot water baseboard
tubing around the room and pipe the domestic water through it. Well water and city water
that runs deep in cool soil will absorb heat from the room as it passes through the loop.
There are two major drawbacks to this method. In summertime the water might be warmer than
desired at the tap, and the loop of piping in the wine cellar will have a tendency to drip
as water vapor condenses on it. The most dependable way is to use a refrigeration unit.
A window or through-the-wall air conditioner can handle the cooling, but will dehumidify
as well, and that is bad. Special equipment is available that will turn the room into a
medium temperature walk-in cooler. These machines are designed to cool without drying the
air. Different outputs allow the unit to meet the demands of the size of the room.